1. Field
The present invention generally relates to communications in a wireless environment. More particularly, the invention relates to message processing in an access terminal in a wireless communication system.
2. Background
Wireless communication systems have developed through various generations, including a first-generation analog wireless phone service (1G), a second-generation (2G) digital wireless phone service (including interim 2.5G and 2.75G networks) and a third-generation (3G) high speed data/Internet-capable wireless service. There are presently many different types of wireless communication systems in use, including Cellular and Personal Communications Service (PCS) systems. Examples of known cellular systems include the cellular Analog Advanced Mobile Phone System (AMPS), and digital cellular systems based on Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), the Global System for Mobile access (GSM) variation of TDMA, and newer hybrid digital communication systems using both TDMA and CDMA technologies.
The method for providing CDMA mobile communications was standardized in the United States by the Telecommunications Industry Association/Electronic Industries Association in TIA/EIA/IS-95-A entitled “Mobile Station-Base Station Compatibility Standard for Dual-Mode Wideband Spread Spectrum Cellular System,” referred to herein as IS-95. Combined AMPS & CDMA systems are described in TIA/EIA Standard IS-98. Other communications systems are described in the IMT-2000/UM, or International Mobile Telecommunications System 2000/Universal Mobile Telecommunications System, standards covering what are referred to as wideband CDMA (WCDMA), CDMA2000 (such as CDMA2000 1xEV-DO standards, for example) or TD-SCDMA.
In wireless communication systems mobile stations, handsets, or access terminals receive signals from fixed position base stations (also referred to as cell sites or cells) that support communication links or service within particular geographic regions adjacent to or surrounding the base stations. Conventionally, each mobile station monitors a control channel that can be used to exchange messages between the mobile station and the base station. The control channel is used to transmit system/overhead messages, whereas traffic channels are conventionally used for substantive communication (e.g., voice and data) to and from the mobile station. For example, the control channel can be used to establish traffic channels, control power levels, and the like, as is known in the art. Generally, when a control channel signal has been received by the mobile station communications modem and is being processed by the mobile station, the mobile station performs power management by lowering or shutting down power to a communication modem, antenna, transmitter and/or receiver. While this conserves power to the mobile station, it may cause problems for delay-sensitive applications that will have to wait for the power startup cycle after processing a response to the control channel signal. Therefore, system engineers may face a trade-off between power conservation and poor responsiveness.